Researchers discover method to unravel malaria's genetic secrets

Jan 25, 2012

The parasite that causes malaria is a genetic outlier, which has prevented scientists from discovering the functions of most of its genes. Researchers at National Jewish Health and Yale University School of Medicine have devised a technique to overcome the genetic oddity of Plasmodium falciparum, the major cause of human malaria. This new approach led them discover a new gene involved in lipid synthesis, and opens the door to further genetic discovery for the entire organism. This should foster a much greater understanding of the parasite, and facilitate discovery of new medications for a disease that infects more than 200 million people and kills nearly 700,000 every year.

"The malarial has been a black box. Our technique allows us to open that box, so that we can learn what genes in the most lethal actually do," said Dennis Voelker, PhD, Professor of Medicine at National Jewish Health and senior author on the paper that appeared in the January 2, 2012 , issue of the . "This could prove tremendously valuable in the fight against a disease that has become increasingly drug-resistant."

The genome of P. falciparum was sequenced in 2002, but the actual functions of many of the organism's genes have remained elusive. One of the primary methods for discovering gene function is to copy a specific gene, insert it into a that is easy to grow, often the yeast Saccharomyces cerevisiae, then draw on the incredible knowledge base about yeast and its abundant genetic variants to discover how that inserted gene changes the organism's biology.

DNA is composed of building blocks with the shorthand designations A,T,C and G. The genome of P. falciparum is odd because it is particularly rich in A's and T's. Because of this A-T-rich nature, P. falciparum genes generally do not function when they are inserted into other organisms. As a result, scientists have been largely stymied when trying to understand the functions of P. falciparum's genes.

It turns out, however, that P. falciparum has a close cousin, P. knowlesi, which shares almost all its genes with P. falciparum, but with fewer A's and T's. As a result, P. knowlesi genes function well when inserted into yeast. Scientists can now insert P. knowlesi genes into yeast, discover their function, and then match them to corresponding genes in P. falciparum, which reveals the function of the malarial parasite's genes.

"This technique could lead to an explosion in knowledge about malaria and the parasite that causes it." said Dr. Voelker.

The researchers used the technique to discover a new gene involved in the synthesis of lipids in cell membranes of P. falciparum. The gene, phosphatidylserine decarboxylase, directs the formation of a protein unique to malarial parasites and is a potential therapeutic target. For example, selective disruption of in P. falciparum, would prevent the organism from making new cell membranes, growing and reproducing in human hosts.

Explore further: Breakthrough understanding of biomolecules could lead to new and better drugs

Provided by National Jewish Health

5 /5 (1 vote)

Related Stories

Profiling malaria-causing parasites

Feb 07, 2011

The majority of fatal cases of malaria are caused by infection with the parasite Plasmodium falciparum. Most at risk are young children and women who are pregnant. A team of researchers, led by Patrick Duffy, at the Nation ...

Discovery provides new drug targets for malaria cure

Jan 11, 2010

Researchers are a step closer to developing new antimalarial drugs after discovering the normal function of a set of proteins related to the malaria parasite protein, which causes resistance to the front-line drug chloroquine. ...

Recommended for you

Breaking benzene

14 hours ago

Aromatic compounds are found widely in natural resources such as petroleum and biomass, and breaking the carbon-carbon bonds in these compounds plays an important role in the production of fuels and valuable ...

How to prevent organic food fraud

16 hours ago

A growing number of consumers are willing to pay a premium for fruits, vegetables and other foods labelled "organic", but whether they're getting what the label claims is another matter. Now scientists studying ...

User comments : 0